Nowadays, when takeout food includes liquid soup or juice, a cup (or bowl) with a lid is used instead of a heatproof plastic bag. After the lid is covered up, although the cup seems airtight, if the cup topples over due to vibration or other factors, the soup or juice will flow out, resulting in a sticky state on the periphery of the cup and thus affecting the appetite. Therefore, a sealing machine has been proposed. As shown in FIGS. 1 and 2, a conventional sealing machine comprises a machine body 10a, a cup seat 11a, a film reel 12a and a waste material reel 13a. The cup base 11a is arranged on the machine body 10a, and can enter or exit an opening in the front side of the machine body 10a. The film reel 12a and the waste material reel 13a are arranged above the machine body 10a. A film 20a is rolled on the film reel 12a, passes through the center of the machine body 10a, and then is wound around the waste material reel 13a. The waste material reel 13a is used to wind waste material and pull the film 20a on the film reel 12a forwards.
When a cup (or bowl) containing food is placed on the cup seat 11a, the film reel 12a and the waste material reel 13a are simultaneously driven to create rotation at a fixed distance, hence performing the actions of cup mouth film sealing and waste material winding. The cup seat 11a is then driven to automatically exit. A push-out device (not shown) is used to butt the film-sealed cup so that a user can take up the cup from the cup seat 11a. This sealing machine not only facilitates the automatic film sealing operation, but also exactly seals the cup. Even if the cup topples over, the soup or juice will not flow out.
However, for the above conventional sealing machine, when an object is detected on the cup seat 11a, the cup seat 11a will be driven to enter the machine body 10a to start the operation of cup mouth film sealing. When the power is not cut off, if one places his hand on the cup seat 11a or an object is placed on the cup seat 11a, the operation of cup mouth film sealing will start to harm the hand or damage the sealing machine.